End closures for cans and other containers and, more particularly, those of the so-called "easy-open" type are, of course, well known in the art. Typically, they include an end wall having a removable panel defined therein by a rupturable score which, upon severance and removal of the panel, provides a dispensing aperture. Generally, score rupture and panel removal are both effected by use of a pull tab having a nose portion at one end and a handle portion at its opposite end. The tab is so mounted on the panel as to be pivotable into contact adjacent the score, so as to initiate severance thereof, and to thereafter facilitate tearing of the panel away from the remainder of the end wall.
Often, the tab must be rigidified when relatively soft or maleable materials, such as aluminum, are employed. As typified by the tab construction illustrated in U.S. Pat. No. 3,863,801, such reinforcement may be effected by downwardly curling the marginal portions of the tab, the outer end of the tab remaining uncurled to provide a relatively sharp tip, for optimum score initiation. However, when a tab of such construction is pivoted to effect opening, the two terminal ends of its curled marginal portions will tend to contact the panel simultaneously with, or before, the tip of the nose. The opening force applied will, as a result, be distributed over an extended area of the panel, thereby precluding the transmission of maximum force to the tip of the tab and, in turn, necessitating the use of an undue amount of effort to effect score initiation. This is not only inconvenient from the consumer's standpoint, but it may, indeed, cause the tab to bend, break and/or be disengaged from the panel.
Accordingly it is an object of this invention to provide a novel can end closure which is simple, highly effective, and of relatively inexpensive construction.
It is also an object of this invention to provide a novel can end closure which affords desirable opening characteristics and maximizes the effectiveness of applied score rupture-initiating force.
It is a more particular object of this invention to provide a novel can end closure of the easy-open type having the foregoing attributes and characteristics.